An architect of the Obama administration 's `` reset '' policy with Russia says he will step down as the American ambassador to the country later this month .

Michael McFaul , U.S. ambassador to Russia since January 2012 , announced Tuesday he 'll leave the post shortly after the Winter Olympics conclude in the southern Russian resort town of Sochi .

McFaul has been a controversial figure in Russia , with some state-run media viewing him with suspicion for his outspoken support of pro-democracy groups . But in his online journal , McFaul said Tuesday that he would miss the job , stressing he was leaving for family considerations .

McFaul said his wife and two sons moved back to California last summer because his oldest son wanted to be home for the last few years of high school .

`` We tried to make a 9,000 kilometer commute work for our family . But after seven months of separation , I simply need to be with my family again , '' McFaul wrote .

`` I will leave Russia reluctantly , '' he said . `` I love this job . It is a tremendous honor to represent my country here . I will miss interacting with my partners in the Russian government and with Russians from all sectors of society . ''

As a Stanford University political science professor , McFaul became one of the best-known American experts on Russia . After advising then-Sen . Barack Obama on Russia during the 2008 presidential campaign , McFaul took a leave from Stanford to become senior director for Russia and Eurasian affairs at the National Security Council .

He helped develop the U.S. `` reset '' policy with Russia , after which the countries signed the New START arms control deal and agreed on a transit treaty allowing the United States and NATO to use a route through Russia into Afghanistan .

On his arrival in Moscow as ambassador in 2012 , he got a rough reception from government-controlled media . An analyst on a government network said McFaul was a `` specialist purely in the promotion of democracy '' and suggested his agenda was dedicated to supporting opposition leaders in the country .

That criticism came as protesters in Moscow were rallying against then-Prime Minister Vladimir Putin , who was running again for president . Putin , who went on to win the presidency , accused the U.S. State Department of stirring things up .

McFaul 's ambassadorship came at a time of strained relations between the two countries , with quarrels over , among other things , Syria 's civil war and the arrival in Moscow of admitted National Security Agency leaker Edward Snowden .

U.S. Deputy National Security Adviser Ben Rhodes said Tuesday that President Obama `` is deeply grateful for Ambassador McFaul 's extraordinary service over the last five years . ''

`` From the White House to Spaso House -LRB- the U.S. Embassy in Moscow -RRB- , Mike helped shape policies that advanced America 's interest -- from the New START treaty , to resupplying our troops in Afghanistan ; from sustaining U.S.-Russian cooperation on negotiations with Iran , to deepening trade and commercial ties , '' Rhodes said .

CNN first learned of McFaul 's planned departure on Twitter .

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Michael McFaul became U.S. ambassador to Russia in 2012

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Russia expert McFaul took leave from Stanford to serve Obama administration in 2009

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McFaul helped develop Obama administration 's first-term `` reset '' policy with Russia

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State-run media criticized McFaul for outspoken support of pro-democracy groups